1. Field of the Invention
The present invention relates to a wireless power transmitting apparatus and method of allocating priorities to a plurality of power receiving apparatuses and automatically transmitting sequentially power to the plurality of power receiving apparatuses according to the allocated priorities without movement of a power transmitting coil or an additional operation of a user to charge the plurality of power receiving apparatuses.
2. Description of the Related Art
Generally, various portable terminals such as a cellular phone, a personal digital assistant (PDA), and the like, have been mounted with a power receiving apparatus charged with a power to supply an operation power thereto. The power receiving apparatus may be charged with a power supplied from an external charging apparatus and supplies the charged power as the operation power to the portable terminal to operate the portable terminal.
The power receiving apparatus may include a battery cell module charged with the power, a charging and discharging circuit charge the power supplied from the external charging apparatus in the battery cell module and discharging the charged power to supply the discharged power to the portable terminal, and the like.
As a scheme of electrically connecting the charging apparatus to the power receiving apparatus, a terminal connection scheme of directly connecting a terminal through which the power is output in the charging apparatus to a terminal to which the power is input in the power receiving apparatus through a cable has been known.
In the terminal connection scheme, the terminal of the charging apparatus and the terminal of the power receiving apparatus have the different potential difference. Therefore, in the case in which the terminal of the charging apparatus and the terminal of the power receiving apparatus are connected to each other or disconnected from each other, an instantaneous discharging phenomenon may occur.
This instantaneous discharging phenomenon causes abrasion of the terminal of the charging apparatus and the terminal of the power receiving apparatus. In addition, in the case in which foreign materials are accumulated in the terminal of the charging apparatus and the terminal of the power receiving apparatus, when the instantaneous discharging phenomenon occurs, the heat may occur in the foreign materials, so there is a risk that an accident such as a fire, or the like, will occur.
In addition, the power charged in the battery cell module charged in the power receiving apparatus is naturally discharged to the outside through the terminal of the power receiving apparatus due to moisture, or the like, so a lifespan of the power receiving apparatus may be decreased and performance of the power receiving apparatus may be deteriorated.
Recently, a wireless power transmitting apparatus wirelessly transmitting the power to the power receiving apparatus has been suggested in order to solve several problems of the terminal connection scheme as described above.
The wireless power transmitting apparatus wirelessly transmits the power in, for example, an electromagnetic induction scheme. In addition, the power receiving apparatus receives the power wirelessly transmitted by the wireless power transmitting apparatus and charges the received power in the battery cell module.
A number of efforts have been conducted in order for the wireless power transmitting apparatus to wirelessly transmit the power stably at high efficiency and in order for the power receiving apparatus to receive the power transmitted by the wireless power transmitting apparatus as much as possible to charge the power in the battery cell module.
There is a case in which a plurality of power receiving apparatuses are seated and charged on a charging station of the wireless power transmitting apparatus. In this case, the power may be transmitted to all of the plurality of power receiving apparatuses through a plurality of power transmitting coils to thereby be simultaneously charged in all of the plurality of power receiving apparatuses.
However, it is very inefficient to transmit the power to all of the plurality of power receiving apparatuses through the plurality of power transmitting coils since the power is transmitted without distinguishing a power receiving apparatus required to be urgently charged. In addition, it takes a more time to charge the power in the case in which the power is transmitted to all of the plurality of power receiving apparatuses through the plurality of power transmitting coils as compared with the case in which the power is sequentially supplied to and charged in the plurality of power receiving apparatuses one by one.
Further, in Japanese Patent Laid-Open Publication No. 2009-273327, a moving unit moving the power transmitting coil is provided under the charging station and allows the power to be transmitted to and charged in the power receiving apparatuses while sequentially moving the power transmitting coil to positions at which the power receiving apparatuses are put.
That is, in the case in which first and second power receiving apparatuses are put at first and second positions of the charging station, respectively, the moving unit moves the power transmitting coil to the first position to charge the power in the first power receiving apparatus. Further, in the case in which the charging of the first power receiving apparatus is completed, the moving unit moves the power transmitting coil to the second position to charge the power in the second power receiving apparatus.
However, even in Japanese Patent Laid-Open Publication No. 2009-273327 described above, the power is transmitted without distinguishing the power receiving apparatus required to be urgently charged, which is very inefficient, and a separate moving unit should be provided in the charging station. In addition, a separate moving control unit, or the like, should be provided in order to control that the moving unit moves the power transmitting coil.